This window creates a new element based window.
size:The size of the window, i.e. how many elements form a window
advance:The advance after how many elements the window moves forward. Default advance is 1, i.e. with every new element
slide:The slide of the window. When using this parameter all elements in the windows will have the same starttimestamp (e.g. helpful for aggregations), while advance will not change the starttimestamp.
partition:The partition attribute of the window. When using this parameter, the window garantees to be opened until size element for this group are read.
Remark: The element window blocks until it reads at least size elements.